The present invention relates to a water jacket for a cylinder head of an engine. More particularly, the present invention relates to a structure of a water jacket for a cylinder head.
In order for an engine to correctly operate and perform efficiently, it must cool off heat generated by combustion and friction of its operating parts. In general, a water-cooled engine is equipped with a water jacket that circulates cooling fluid, such as cooling water, around the cylinder block and cylinder head of an engine. The circulating cooling water cools off any heat generated by operation of the engine.
Current water jackets for circulating cooling water about a cylinder head of an engine have a number of drawbacks. One such drawback is that they do not effectively cool the area in and around cylinders"" exhaust ports. Accordingly, a water jacket that effectively cools the area in and around cylinders"" exhaust ports would be highly desirable.
In accordance with one embodiment of the present invention, a water jacket for a cylinder head includes a restricted portion for reducing the flow in a lower path, such that cooling water flows from the lower path to a higher path through a control path. The restricted portion is disposed near to where the lower path meets with the central path.
Preferably, the water jacket has a restricted portion along a lower path near to where said lower path meets a central path. The restricted portion reduces the flow of cooling fluid through the lower path. The lower path and the higher path are substantially parallel to each other. Also, the central path is substantially parallel to a cylinder. The lower path and the higher path are substantially perpendicular to the central path. The lower path and the higher path are similar, but for the restricted portion. In a preferred embodiment, the restricted portion is an indentation in one side of the lower path. Also in a preferred embodiment, the lower path and the higher path define two boundary edges of two exhaust ports of a cylinder, while the central path separates said the exhaust ports.
According to another embodiment of the invention, a water jacket includes at least two exhaust ports configured to exhaust combusted gases from a cylinder. The water jacket also defines a lower path, an higher path, and a central path. The higher path is configured for circulating cooling fluid above the at least two exhaust ports. The lower path is configured for circulating cooling fluid below the at least two exhaust ports. Also, the central path fluidly couples the lower path to the higher path. The central path also separates the at least two exhaust ports from one another. The central path is also configured for circulating cooling fluid between said at least two exhaust ports. A restricted portion is formed in the lower path on one side of said central path. The restricted portion is configured to restrict flow through the restricted portion of the lower path, thereby forcing cooling fluid through the central path. In a preferred embodiment, the restricted portion is formed to one side of where the low portion meets the central portion. The restricted portion reduces the flow of cooling fluid through the lower path. The lower path and the higher path are substantially parallel to each other. Also, the central path is substantially parallel to a cylinder. The lower path and the higher path are substantially perpendicular to the central path. The lower path and the higher path are similar, but for the restricted portion. In a preferred embodiment, the restricted portion is an indentation in one side of the lower path. Also in a preferred embodiment, the lower path and the higher path define two boundary edges of two exhaust ports of a cylinder, while the central path separates said the exhaust ports.